1. Technical Field
The present invention relates to a recording method and a recording apparatus in which a dot missing portion due to nozzles of ejection abnormality is made inconspicuous by dots due to normal nozzles when performing recording by forming the dots by ejecting liquid such as ink from the nozzles in the course of moving a recording section.
2. Related Art
Conventionally, as this kind of the recording apparatus, an ink jet type printer, which performs printing of a document or an image on a medium such as a sheet by forming dots by ejecting ink (an example of liquid) from a plurality of nozzles included in a recording head, has been known. As such a printer, for example, a serial printer, a lateral type printer, and the like have been known, in which in the middle of moving of a carriage having the recording head in a scanning direction intersecting a nozzle column direction of the recording head, the image and the like are printed on the medium by ejecting liquid droplets (ink droplets) from the nozzles.
However, if the nozzles cause ejection abnormality, a white streak, in which the dots miss along the scanning direction, occurs on a printed image on the medium and printing quality is lowered. If printing quality does not satisfy certain requirements and printing is failed due to presence of such a white streak, the ink and the medium such as the sheet which are consumed in printing are wasted.
For example, a recording apparatus, which includes a detection device detecting abnormal nozzles based on a read image by printing a test pattern at a portion other than a printing region and optically reading the test pattern, is disclosed in JP-A-2012-71568. However, since the abnormal nozzles cannot be detected during printing, previous printing is likely to have failed due to the presence of a white streak and the like, even if the abnormal nozzles can be detected by printing of the test pattern.
Furthermore, a recording method in which if the abnormal nozzles are detected during moving of the recording head, the dot missing portion due to the abnormal nozzles is complemented with dots by normal nozzles in the next scanning of the recording head after transporting in which a transport amount of the medium is changed is disclosed in International Publication No. WO00/38927. According to the recording method, since a white streak can be reduced by complementation of the dots using the normal nozzles, it is possible to reduce a frequency of failure of printing.
Furthermore, for example, recording methods in which if the abnormal nozzles (non-ejecting nozzles) occur during moving of the recording head, missing of the dots is made inconspicuous by increasing the recording density of adjacent dots by increasing an ejecting amount of dots (pixels) adjacent to dots which were to be originally printed by the abnormal nozzles are disclosed in JP-A-2005-67049 and JP-A-9-24609.
However, in the recording method described in International Publication No. WO00/38927, since next scanning for complementing the dot missing portion due to the abnormal nozzles is supplementary scanning performing only complementation of the dots, a throughput of recording is reduced.
On the other hand, according to the recording methods described in JP-A-2005-67049 and JP-A-9-24609, supplementary scanning for complementing the dot missing portion by the dots is not increased, but since white streak is inconspicuous by increasing the recording density by increasing the ejecting amount of the dots adjacent to the dots which have to be formed by the abnormal nozzles, print quality is slightly lowered compared to print quality before the abnormal nozzles occur.